How Skin Moles Work

A melanoma begins to develop when melanocytes, the same cells that cause moles, begin dividing without control or predictable order. These abnormal cells then invade and destroy the cells around them, causing malignant tissue to grow on the surface of the skin. A melanoma can begin as an existing mole, or it can develop as a new skin growth [source: National Cancer Institute].

While most moles are completely harmless, moles are a risk factor for melanoma. Those with many ordinary moles (more than 50) and those with dysplastic nevi are more susceptible to melanoma. Other risk factors include a family history of melanoma, exposure to UV radiation, a history of severe or blistering sunburns, freckles and pale skin [source: National Cancer Institute].

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Doctors advise individuals concerned about melanoma to follow the ABCDE rule. This rule indicates that if a person has a mole that falls into any of the following categories, he or she should consult a dermatologist:

A is for "asymmetry," which refers to a mole that doesn't appear the same on each side

B is for "border," referring to a mole with a blurry or jagged edge

C is for "color," meaning moles that change color, either darkening or lightening, or that have the appearance of multiple colors

D is for "diameter," referring to a mole that is larger than .25 inches (.64 cm) in diameter, or about the size of a pencil eraser

E is for "elevation," indicating a mole that is raised above the skin and has a rough surface

In addition to the ABCDE symptoms described above, any translucent, pearl-shaped growth or mole that has begun to grow, bleed or itch requires consultation with a dermatologist [source: American Academy of Dermatology].

The most important thing to remember about melanoma is that it can be cured with minimal surgery when caught early [source: National Cancer Institute]. For this reason, individuals should watch for any signs of abnormality in moles.

Read on to learn more about the processes of mole removal.

Other Skin Pigment Conditions

Several other skin conditions may resemble moles. Freckles are the most common skin discoloration aside from moles. Freckles rarely grow larger than the size of a pea and are never raised. In middle age, brown, wartlike growths, known as seborrheic keratoses, can appear. Actinic lentigines, more commonly known as "liver spots" or "age spots," often occur among elderly individuals. All of these skin pigmentations are noncancerous [source: American Academy of Dermatologists].